If you want another take on wireless network security, here’s an excellent article by Andy Atkinson on the topic:

5 minute wireless network security

Everyone agrees that security is important, no one agrees on how much effort should go into securing your home wireless LAN. The good news is that there are some basic steps you can take that require just 5 minutes of your time. In this article I will show you how to add various layers of security to your home wireless LAN. The specific wireless router I will be using is a Linksys WRT54G, a popular 802.11g (54 Mbps) device. Most wireless routers use similar terminology so you will likely be able to find some useful information in this article even if you don’t have this specific Linksys router.

And if you need to see the big picture on wireless in your home or small office, this article by Bradley Mitchell is also great:

Setting up a home wireless network

Many folks setting up wireless home networks rush through the job to get their Internet connectivity working as quickly as possible. That’s totally understandable. It’s also quite risky as numerous security problems can result. Today’s Wi-Fi products don’t always help the situation as configuring their security features can be slow and non-intuitive. The recommendations below summarize the steps you should take, in order to importance, to improve the security of your home wireless LAN.